1. Field
Example embodiments relate to a semiconductor device and methods of manufacturing and operating the same. Other example embodiments relate to a resistive random access memory device and methods of manufacturing and operating the same.
2. Description of the Related Art
A resistive random access memory (RRAM) device is a non-volatile memory device that changes the resistance of a material, for example, a transition metal oxide, at a particular voltage. When a voltage equal to or greater than a set voltage is applied to a resistance-changing material, the resistance of the resistance-changing material may be reduced, which corresponds to an ON state. When a voltage equal to or greater than a reset voltage is applied to the resistance-changing material, the resistance of the resistance-changing material may be increased, which corresponds to an OFF state. A multi-layer cross point RRAM has an advantage of higher integration due to its simpler cell structure.
A storage node of a RRAM has a structure in which a lower electrode, a resistance-changing layer formed of a resistance-changing material, and an upper electrode may be sequentially stacked. A conventional RRAM may use nickel oxide (NiOx) as the resistance-changing layer, and platinum (Pt) may be used as the lower and the upper electrodes.